Levels and trends of immigration by sex, Manhiça, 1998 to 2005. Calculated from the Manhiça DSS data. Imigration Males – immigration rate per 1000 person-years, males Manhiça DSS. Imigration Females – immigration rate per 1000 person-years, females Manhiça DSS. Immigration rate ratio comparing males to females, after controlling for age was 1.132, 95% CI = 1.080 - 1.119 and P = 0.007.